A man, an ox and one day

Dad and I were talking about the amount of fertilizer to use on his vegetable garden and we had been given the amount in terms of acres. After doing the calculations based on square footage (an acre is 43,560 square feet), I wondered where that form of land measurement came from anyway. Wikipedia to the rescue…

The acre was selected as approximately the amount of land tillable by one man behind an ox in one day. This explains its definition in terms of the non-square one-chain by one-furlong parcel of land; a long narrow strip of land is more efficient to plough than a square plot, since the plough does not have to be turned so often.